Abstract
Purpose
To investigate the impact of varicocele on pregnancy and live birth outcomes in men with clinical varicocele in controlled studies.
Materials and Methods
A comprehensive literature search was conducted across the PubMed and Scopus databases using Boolean operators, covering all available records from each database's inception through June 30, 2024. The inclusion criteria focused on controlled studies that compared pregnancy-related outcomes—including pregnancy, miscarriage, and live birth rates—between men with clinical varicocele and those without. These studies included participants attempting conception either spontaneously or through assisted reproductive techniques.
Results
Out of 3,532 articles screened, only two controlled studies met the inclusion criteria. The findings revealed no significant differences between men with and without varicocele in terms of time to achieve pregnancy (5.3 vs. 5.4 months, respectively; p=0.92) or the proportion of men who had previously conceived with their partner (58.9% vs. 63.4%, respectively; p=0.47). However, a significant difference was observed in live birth rates, with men with varicocele showing a lower rate than those without (71.2% vs. 76.4%; p=0.04).
Conclusions
The relationship between varicocele and conception remains contentious, primarily due to the limited number of controlled studies available for analysis. Despite an extensive systematic search for controlled studies comparing pregnancy-related outcomes in men with and without clinical varicocele, only two studies met the inclusion criteria. These studies showed no significant differences in time to achieve pregnancy or previous conception rates between the two groups. However, men with varicocele exhibited a slightly lower, statistically significant, live birth rate compared to men without varicocele. This highlights the need for further research on this topic to provide evidence-based guidance on the impact of varicocele on fertility outcomes.
Keywords: Infertility, male; Live birth; Pregnancy; Spermatozoa; Varicocele
INTRODUCTION
Infertility is a widespread global issue with profound and lasting effects on both male and female partners. Recent data from Nugent and Chandra [1] indicate that 11.4% of men aged 15 to 49 years experienced infertility (subfertility or sterility) between 2015 and 2019. Additionally, a WHO prevalence study estimated a pooled lifetime prevalence of male infertility at 17.5% (95% confidence interval [95% CI]: 15.0–20.3) [2]. Alarmingly, Levine et al [3] demonstrated a 76.9% increase in male infertility prevalence from 1990 to 2019, irrespective of geographical region. Among the numerous causes of male infertility, varicocele remains one of the most common and extensively studied etiologies.
Varicocele occurs in 35% of men with primary infertility and upwards of 81% of men with secondary infertility [4]. Yet, despite the significant prevalence of varicocele in the male population, a concrete understanding of the pathophysiologic correlation with male infertility remains largely unresolved. Pathogenesis of varicocele is multifactorial and includes anatomicphysiologic causes such as scrotal hyperthermia, hypoperfusion of the testis, metabolic reflux, and hormonal dysfunction (Leydig cell damage and resulting hypogonadism). Recent evidence also indicates varicoceles may cause damage to sperm proteins [5], the creation of anti-sperm antibodies [6], the generation of radical oxygen species leading to oxidative stress [7], and increased sperm DNA fragmentation (SDF) [8].
No single factor is likely solely responsible for the effects of varicocele on male infertility, but rather a summation of the aforementioned influences. Varicocele has a well-established effect on semen parameters [9]; however, its impact on pregnancy and assisted reproductive technologies (ARTs) outcomes is less clear and notoriously difficult to understand, with studies showing conflicting results.
The development and refinement of the field of ART have allowed many couples struggling with infertility a viable means of attaining pregnancy. As the technology has blossomed, the indications for in-vitro fertilization (IVF) and intracytoplasmic-sperm-injection (ICSI) have broadened and include mild to moderate semen abnormalities failing conservative treatment, severe oligospermia or azoospermia, necrospermia, globozoospermia, idiopathic infertility [10].
While ART is effective, there is growing evidence that the presence of varicocele can negatively affect ART outcomes. Varicoceles are hypothesized to have a negative effect on ART pregnancy rates largely due to elevated levels of SDF, with improvements in SDF and oxidative stress noted after repair in two large meta-analyses [11,12]. This can, in turn, translate to improved pregnancy and live birth rate outcomes, as evidenced by several studies. In a meta-analysis conducted with nine studies, men with varicocele repair showed a significant improvement in fertilization rate (mean difference 10.9%), clinical pregnancy rate (odds ratio [OR]: 1.38), and live birth rate (OR: 2.07) compared to men who did not undergo varicocele repair [13]. However, contradictory evidence from Pasqualotto et al [14] also found that varicocelectomy before ICSI did not improve pregnancy rates or decrease miscarriage rates compared to men who did not undergo varicocele repair.
There is conflicting data in the literature regarding varicoceles and their influence on pregnancy-related outcomes. Although varicocele repair may improve sperm quality and fertility [15], it is uncertain whether men with varicocele have worse pregnancy outcomes compared to men without varicocele. This has become even more muddled in the IVF/ICSI era as some reproductive specialists use IVF/ICSI to overcome male factor infertility due to varicocele. Given the extremely high prevalence of varicocele in men at the population level and a nuanced understanding of how this common condition impacts pregnancy outcomes is still lacking, the purpose of this systematic review is to investigate the impact of varicocele on clinical pregnancy and live birth outcomes in men with clinical varicocele compared to men without varicocele, looking for conception either spontaneously or through ART.
MATERIALS AND METHODS
1. Search strategy
This systematic review was carried out following the guidelines outlined in the Meta-Analysis and Systematic Reviews of Observational Studies (MOOSE) and the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). The review has been registered with PROSPERO under the registration number CRD4202458804.
A literature search was conducted across PubMed, Cochrane, and Scopus databases via Boolean operators from each database inception to June 30, 2024. The following search terms were used in the PubMed database: "varicocele*" {All Fields} AND ("pregnancy"{All Fields} OR "miscarriage" {All Fields} OR "live birth"{All Fields} OR "pregnancy loss" {All Fields}). For Scopus searches, we used the search terms: varicocele AND ((pregnan*) OR (miscarriage) OR (pregnancy AND loss) OR (live AND birth) OR (art) OR (assisted AND reproductive AND technique) OR (icsi) OR (intracytoplasmic AND sperm AND injec*) OR (ivf) OR (in AND vitro AND fertil) OR (iui) OR (intra AND uterine AND insem*)) AND (LIMIT TO (DOCTYPE, "ar")) AND (LIMIT-TO (SUBJAREA, "MEDI"). Both English and non-English articles were included in the search.
2. Selection criteria
Our systematic review included controlled studies on adult men with clinical varicocele carried out until June 30, 2024, that evaluated pregnancy-related outcomes (pregnancy, miscarriage, live birth rates) achieved spontaneously or through ART. All the eligible studies were chosen based on the Population, Exposure, Comparison/Comparator, Outcomes, and Study design (PECOS) framework (Table 1) [16]. The following studies were excluded: studies on adolescents of subclinical varicocele with no varicocele in the patient group or with varicocele or varicocele repair in the control group, female factor infertility, or other associated pathology (e.g. vasectomy, testicular trauma, torsion, epididymo-orchitis, hypogonadism, etc), studies conducted, studies conducted in animals or in vitro, non-original studies, and case reports or case series (Table 1). Studies were initially screened for inclusion using the PECOS filter by reviewing their titles and abstracts. The full text was thoroughly examined if the abstract did not clearly state whether the study provided relevant data for the meta-analysis. Researchers underwent systematic training exercises before the study began to ensure a standardized evaluation process, as described elsewhere [17]. Two independent authors screened all retrieved studies by reading their titles and abstracts. A third author resolved conflicts.
Table 1. Selection criteria for studies included in the systematic review and meta-analysis using the PECOS model.
| Category | Inclusion criteria | Exclusion criteria |
|---|---|---|
| Population | Men over the age of 18 trying to conceive | Patients with azoospermia, adolescents, men from couples with female factor infertility, treatment for infertility (AOX, SERMs, AIs, FSH or other associated pathology [e.g., vasectomy, testicular trauma, torsion, epididymo-orchitis, hypogonadism, etc]) |
| Exposure | Clinical varicocele | - |
| Comparator | No varicocele | - |
| Outcome | Pregnancy rate (spontaneous or after ART) | Different outcome |
| Live birth rate (spontaneous or after ART) | ||
| Study design | Controlled studies with any experimental design | Case reports, case series, conference papers, reviews, book chapters, animal studies, in vitro studies |
AOX: antioxidants, SERMSs: selective estrogen receptor modulators, AIs: aromatase inhibitors, FSH: follicle-stimulating hormone, ART: assisted reproductive technique.
3. Data extraction
Data from articles that met our inclusion criteria were extracted and recorded into a standardized spreadsheet. A second researcher reviewed each entry for accuracy. Any discrepancies in data extraction were resolved by consulting a third experienced researcher. The following information was collected: study design, age of patients, varicocele grade, duration until followup assessment, number of patients and controls, number of pregnancies, miscarriages, live births, semen analysis report, and the use of ART.
4. Quality assessment
Independent researchers working in pairs assessed the quality of evidence (QoE), with a third researcher reviewing their findings (Supplement Table 1). Observational studies were evaluated using the Cambridge Quality Checklist [18]. Variables were categorized as correlates, risk factors, and causal risk factors. Correlates were determined based on construct and statistical conclusion validity, while risk factors (for longitudinal studies) and causal risk factors were evaluated based on the correlation between variables that should have occurred prior to the outcome. For randomized controlled trials (RCTs), the assessment followed the Consolidated Standards of Reporting Trials (CONSORT) guidelines [19]. Observational studies were rated on the Cambridge Quality Checklist with a score range of 0–5 indicating low QoE, 6–10 for moderate QoE, and 11–15 for high QoE. RCTs were evaluated using CONSORT scores to determine the QoE. Specifically, CONSORT assigns a score up to 25, categorizing the risk of bias as follows: 0–8 indicates high risk, 9–16 indicates moderate risk, and 17–25 indicates low risk.
RESULTS
According to the defined search strategy, 3,532 papers were initially retrieved. After automatic removal of 238 duplicates and manual exclusion of an additional 3 duplicates, 3,291 papers were screened based on their titles and abstracts. Of these, 3,093 papers were excluded as they were unrelated to the review's aim. The remaining 198 full-text papers were assessed for eligibility, resulting in the exclusion of 196 studies. Only two articles met the inclusion criteria [20,21].
Fig. 1 illustrates the PRISMA flow diagram summarizing the literature search process. Table 2 provides the characteristics of the two included retrospective studies. Notably, no RCTs were identified.
Fig. 1. PRISMA flowchart of the literature search.
Table 2. Studies evaluating pregnancy outcomes in patients with varicocele.
| Author (year) | Type of study | Group | Age (y), mean±SD | Grade of varicocele | Spontaneous clinical pregnancy, n (%) | Spontaneous clinical pregnancy, n (%) |
|---|---|---|---|---|---|---|
| Redmon et al (2019) [20] | Prospective | Varicocele group: n=56 | Varicocele: 33±5 | Grade I/II/III (clinical) | Varicocele group: 33 (58.9) | |
| Control group: n=653 | Control: 31±6 | Control group: 414 (63.4) | ||||
| Verhovsky et al (2018) [21] | Retrospective | Varicocele group: n=1,758 | Overall: 25±1.8 | Not specified | Varicocele group: n=1,252 (71.2) | |
| Control group: n=9,286 | Control group: n=7,090 (76.4) |
SD: standard deviation.
1. Clinical pregnancy
Only the study by Redmon et al [20] investigated spontaneous clinical pregnancy outcomes in men with and without varicocele. Their findings demonstrated a smaller left testicular volume and reductions in several semen parameters, including total sperm count and total motile sperm count, among men with varicocele. However, no significant differences were observed between men with and without varicocele regarding the time to achieve pregnancy (5.3 vs. 5.4 months, respectively; p=0.92) or the proportion of men who had previously conceived with their partner (58.9% vs. 63.4%, respectively; p=0.47).
2. Live birth
Verhovsky et al [21] evaluated spontaneous live birth rate in four groups: men with varicocele who underwent preventive varicocelectomy, infertile men with varicocele who underwent secondary surgery, men with varicocele who did not undergo surgery, and healthy controls. We considered the data from the nonsurgical group (n=1,758) and the healthy controls (n=9,286). The nonsurgical group showed a lower live birth rate than the healthy controls (71.2% vs. 76.4%; p=0.04), suggesting the negative impact of varicocele on live birth rate.
DISCUSSION
1. Published systematic review and meta-analyses reporting the impact of varicocele repair on pregnancy outcomes
Our work focused on systematically exploring the impact of varicocele on pregnancy-related outcomes by comparing them in men with and without varicocele. Surprisingly, only two studies satisfied our inclusion criteria, making our results not generalizable.
Although the evidence on the impact of varicocele on pregnancy-related outcomes is scarce, more studies are currently available investigating how its repair can improve pregnancy outcomes. In a meta-analysis including seven RCTs performed by Kim et al [22], they found varicocelectomy improved pregnancy rates with an OR of 4.15 (95% CI, 2.31–7.45; p<0.001). Similarly, a meta-analysis by Baazeem et al [23] found that among 4 included RCTs, of the 192 men randomized to surgical varicocele repair, OR of 2.1 (95% CI, 1.31–3.38; p=0.002) was found. In a meta-analysis by Kroese et al [24], spontaneous pregnancy was evaluated in 10 studies on men randomized to surgery or embolization of varicocele. Among 894 included men, 181 pregnancies were noted, which is similar in percentage to those reported by Baazeem et al [23]. This equates to an OR 1.47 (95% CI, 1.05–2.05; p=0.03) with a number needed to treat 17; however, the overall QoE was low, and there was significant bias among included studies. Furthermore, live birth rates were not reported as a primary outcome, somewhat limiting the scope of these findings [24].
Finally, recent work by Persad et al [25] looked at fertility outcomes in men with treated varicocele versus untreated varicocele. In the two studies included in this analysis, the live birth rate for surgical treatment ranged from 3% to 38%, with a risk ratio of 6.50. Treatment in men with varicocele and abnormal semen analyses had an improvement between 26% and 64%, arguing that treatment may indeed improve the chance of pregnancy [25]. These findings are summarized in Table 3.
Table 3. Comparison of meta-analyses studying varicocelectomy and pregnancy, live birth outcomes.
| Author (year) | Type of study | Included study (n) | Pregnancy outcomes after varicocele treatment | Live birth outcomes (%) | ART clinical pregnancy | |
|---|---|---|---|---|---|---|
| Kroese et al (2012) [24] | Meta-analysis | 10 (10 RCTs) | Normal SA (10 RCTs) | Not reported | Not reported | |
| OR=1.47 (95% CI: 1.05–2.05, p=0.03; I2=67%) | ||||||
| NNT 17 | ||||||
| Abnormal SA (5 RCTs) | ||||||
| OR=2.39 (95% CI: 1.56–3.66, p=0.03; I2=64%) | ||||||
| Kim et al (2013) [22] | Meta-analysis | 7 (7 RCTs) | Overall (7 RCTs) | Not reported | Not reported | |
| OR=1.9 (95% CI: 0.77–7.66) | ||||||
| Abnormal SA (3 RCTs) | ||||||
| OR=4.15 (95% CI: 2.13–7.45, p<0.001; I2=20.4%) | ||||||
| Baazeem et al (2011) [23] | Review and meta-analysis | 4 (4 RCTs) | OR=2.1 (95% CI: 1.31–3.38, p=0.002; I2=14.60%) | Not reported | Not reported | |
| Persad et al (2021) [25] | Meta-analysis | 13 (13 RCTs) | Treatment vs. non-surgical, non-radiologic, or no treatment | Live birth rate (2 RCTs) RR=2.27 (95% CI: 0.19–26.96) |
Not reported | |
| 22%–48% (RR=1.55, 95% CI: 1.06–2.26; I2=74%), 22%–48% vs. 21% | ||||||
RCT: randomized control trial, OR: odds ratio, CI: confidence interval, NNT: number needed to treat, SA: semen analysis, RR: relative risk, ART: assisted reproductive technique.
2. What do the guidelines recommend on the treatment indications in men with clinical varicocele who desire children?
Treatment recommendations for men with clinical varicocele who desire children are well-established in various professional society guidelines. Varicocele is addressed in the guidelines with clear treatment indications based on clinical evaluation and fertility goals. Leading organizations such as the American Urological Association (AUA)/American Society for Reproductive Medicine (ASRM) [26], and the European Association of Urology (EAU) [27] provide up-to-date surgical indications for varicocele repair. Other societies, including the Canadian Urological Association (CUA), European Society of Human Reproduction and Embryology (ESHRE), and Urological Society of Australia and New Zealand (USANZ), either align with or endorse there recommendations (Table 4).
Table 4. Summary of all professional society guidelines on the indications for varicocele repair in infertile men.
| Treatment indications | Management insight | Key differences | Actual statement | |
|---|---|---|---|---|
| American Urological Association (AUA)/American Society for Reproductive Medicine (ASRM) [26] | a) Clinically palpable varicocele b) Infertility c) Abnormal semen parameters d) Desire for future fertility |
- Varicocele repair is aimed at improving semen parameters and enhancing natural fertility. | Does not recommend treatment for subclinical varicocele. | - Surgical varicocelectomy should be considered in men attempting to conceive, who have palpable varicocele(s), infertility, and abnormal semen parameters, except for azoospermic men. (Moderate Recommendation; Evidence Level: Grade B) - Clinicians should not recommend varicocelectomy for men with nonpalpable varicoceles detected solely by imaging. (Strong Recommendation; Evidence Level: Grade C) |
| Updates to male infertility: AUA/ASRM Guideline (2024) [28] | a) Clinically palpable varicocele b) Infertility c) Abnormal semen parameters or elevated sperm DNA fragmentation d) Desire for future fertility |
- Varicocele correction can lead to improved semen quality and reduced sperm DNA damage, potentially enabling couples to achieve pregnancy through less invasive, lower-intensity, and more cost-effective methods. This may include conceiving via IUI instead of IVF, or achieving pregnancy naturally through intercourse rather than relying on IUI. | Addition of elevated sperm DNA fragmentation as an indication for varicocele repair. | - Male reproductive experts should evaluate patients with a complete history and physical examination as well as other-directed tests, when indicated by one or more abnormal semen parameters or presumed male infertility. (Expert Opinion) |
| European Association of Urology (EAU) [27] | a) Palpable varicocele b) Abnormal semen parameters c) Documented infertility d) Men seeking fertility improvement |
- Varicocele repair has been shown to improve pregnancy rates and increase sperm concentration in adult men with infertility and abnormal semen analysis, though its effects on sperm motility and morphology are less well-established. Additionally, varicocele is linked to SDF, and treatment has been demonstrated to lower SDF levels, potentially enhancing ART outcomes. | Recommends against treating subclinical varicocele &in normal semen parameters. Emphasizes treatment only for men seeking fertility improvement. |
- Treat infertile men with a clinical varicocele, abnormal semen parameters and otherwise unexplained infertility in a couple where the female partner has good ovarian reserve to improve fertility rates. (Strong) - Varicocelectomy may be considered in men with raised DNA fragmentation with otherwise unexplained infertility or who have suffered from failures of assisted reproductive techniques including recurrent pregnancy loss, failure of embryogenesis and implantation. (Weak) |
| European Society of Human Reproduction and Embryology (ESHRE) | There are no direct guidelines from ESHRE that specifically address the relationship between varicocele repair and pregnancy outcomes. | |||
| Canadian Urological Association (CUA) | The CUA does not have specific guidelines solely dedicated to varicocele and its impact on pregnancy. The CUA tends to follow general principles shared by international urological guidelines, highlighting the importance of varicocele repair in men with abnormal semen parameters and infertility. | |||
IUI: intrauterine insemination, IVF: in vitro fertilization, ART: assisted reproductive technology, SDF: sperm DNA fragmentation.
There is a broad agreement across these guidelines that varicocele repair should be offered to men with infertility (documented for at least 12 months) who desire children, have a clinically palpable varicocele on physical examination, and demonstrate abnormal semen parameters, especially when the female partner is healthy, and no other causes of infertility are identified. Conversely, treatment is not recommended for subclinical varicocele (detected only by ultrasound), men with normal semen parameters or those without fertility concerns. Surgical intervention is considered to enhance natural conception potential before pursuing more costly options such as IVF [26,27,28].
These guidelines (Table 4) emphasize the importance of shared decision-making between the patient and healthcare provider, considering fertility goals, semen analysis findings, and the presence of a palpable varicocele. Overall, they reflect a consensus favoring varicocele repair to improve the chances of natural conception before opting for ART, especially when semen quality is compromised.
3. Clinical significance of our results
Even though the pregnancy rate was similar between the varicocele group and the control group in the study by Redmon et al [20], the presence of varicocele may decrease the live birth rate, supporting the importance of treatment for improving fertility outcomes. In contrast, the study by Redmon et al [20] demonstrated that although varicocele caused deterioration in sperm parameters and reduced testicular volume, the pregnancy rate and time to conception were not significantly different between those who had varicocele and those who did not. However, it must be considered that Redmond’s study [20] included men whose female partners were currently pregnant, which represents a selection bias. Additionally, factors such as the personal will to achieve a pregnancy or the unknown proportion of pregnancies achieved by fertility treatment should be acknowledged as limitations of both the studies herein included.
The findings of this study, which show similar pregnancy rates regardless of varicocele presence, suggest that varicocele may not always affect fertility. This supports the well-established observation that many men with varicoceles are fertile or, if sub-fertile, can compensate through a fertile partner. However, other studies indicate that varicocele repair can significantly improve the pregnancy rate [22,23,24], highlighting that varicocele can impair fertility in specific individuals. Therefore, while not all men with varicocele require surgery, as many can conceive naturally, there could be a role for varicocele repair in couples who have been trying to conceive for a reasonable period without success. Evidence for such a selected recommendation for the repair of varicoceles comes from the study by Giagulli et al [29], which found no difference in pregnancy rate between men who underwent varicocele repair and those who did not in an unselected group. However, when results were analyzed in a sub-group of men who had been infertile for over two years, the pregnancy rate was significantly higher in the operated group. This underscores the importance of considering the duration of infertility when evaluating the need for varicocele repair. Currently overlooked in many guidelines, this temporal aspect should be incorporated into recommendations for varicocele treatment, and future studies should account for infertility duration when assessing varicocele repair outcomes.
Inconsistencies in the data, mainly related to the low number of studies, suggest that our current knowledge of the impact of varicocele on pregnancy-related outcomes and our ability to make evidence-based recommendations is limited. While focused studies are needed to answer the question of whether varicocele impairs the ability to reach a pregnancy, individualized treatment strategies that consider both male and female infertility factors are essential. These strategies should account for factors such as the severity of the varicocele, the presence of concurrent male and female infertility issues, and the couple’s specific reproductive goals.
In conclusion, this review highlights the need for more extensive and robust studies to address existing knowledge gaps. Such studies would provide more substantial evidence and help establish more straightforward clinical guidelines, ultimately improving conception rates for men struggling with infertility due to varicocele.
4. SWOT analysis
The SWOT (strengths, weaknesses, opportunities, and threats) analysis of the impact of varicocele on conception, as shown in Fig. 2, highlights several critical aspects. One of the primary strengths of this study lies in its strict selection criteria, which ensured high relevance and comparability of the included data. To evaluate the impact of varicocele on pregnancy-related outcomes, the most effective approach involved comparing varicocele patients to a population of healthy controls. Using this methodology, one study identified a detrimental effect of varicocele on reproductive outcomes, emphasizing the significance of targeted investigations. However, our study also showed notable weaknesses. These included inconsistent data on the impact of varicocele on pregnancy outcomes, the low quality of available evidence, and considerable variability in study designs and patient selection criteria. Such limitations complicate clinical decision-making and delay the establishment of standardized treatment approaches. An important opportunity identified in this analysis is the recognition of a significant gap in the current literature on this topic. This highlights the need for further high-quality research to better understand the relationship between varicocele and reproductive outcomes, which could advance clinical practice and provide clearer guidance for clinicians. Despite these opportunities, certain threats were also evident. The lack of definitive treatment guidelines for managing varicocele in the context of pregnancy outcomes presents a challenge, leading to variability in clinical practice. Additionally, the potential for overtreatment, such as performing preventative surgery on all men with varicocele, raises concerns about patient safety and the efficient use of healthcare resources. The SWOT analysis underscores the importance of addressing these gaps and challenges to improve understanding, patient care, and reproductive outcomes.
Fig. 2. Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis. SRMA: systematic review and meta-analysis, ART: assisted reproductive technology, Vx: varicocele.
CONCLUSIONS
Varicocele is very prevalent in the general population of men, but its impact on infertility and pregnancy outcomes remains a topic of debate. Several studies have identified the impact of varicocele on sperm parameters. However, information is scarce in the literature about the effect of varicocele on pregnancy-related outcomes. While studies have shown the benefit of varicocele repair on live birth rate compared to untreated patients, few studies have assessed the impact of untreated varicoceles on pregnancy-related outcomes compared to healthy controls. Despite a comprehensive search strategy, we could identify only two controlled studies addressing this issue. One study found that the presence of a varicocele did not affect the time to achieve pregnancy, and previous conception rates were the same between men with and without a varicocele. However, another study found that men with varicoceles achieved a slightly lower, but statistically significant, live birth rate compared to men without varicoceles. To the best of our knowledge, this represents the first systematic review and meta-analysis specifically assessing pregnancy-related outcomes in men with and without varicocele. The paucity of available data indicates the need for more well-designed, high-quality, large-scale studies to improve our understanding of the impact of varicoceles on pregnancy and live birth rates, which would assist in developing stronger guidelines for managing infertile couples with a varicocele.
Acknowledgements
None.
Footnotes
The researchers contributing to this publication are members of the Global Andrology Forum (GAF), based in Moreland Hills, OH, USA. GAF operates under the Global Andrology Foundation, a non-profit organization registered in Innsbruck, Austria.
Conflict of Interest: The authors have nothing to disclose.
Funding: None.
- Conceptualization: RC, SC, AA.
- Methodology: RC, SC.
- Data curation: RC.
- Writing-Original draft preparation: CG, LH, RC, KK, AR, SC.
- Supervision: AA.
- Validation: SC, R Shah.
- Writing-Reviewing and Editing: All authors.
Supplementary Materials
Supplementary materials can be found via https://doi.org/10.5534/wjmh.250023.
Results of quality of evidence assessment
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Associated Data
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Supplementary Materials
Results of quality of evidence assessment